Improve main activity user experience

app/src/main/java/io/bartek/MainActivity.kt

@@ -6,8 +6,10 @@ import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
-import android.widget.Button
+import android.widget.TextView
+import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
+import androidx.appcompat.widget.AppCompatImageButton
 import androidx.localbroadcastmanager.content.LocalBroadcastManager
 import io.bartek.preference.PreferencesActivity
 import io.bartek.service.ForegroundService
@@ -15,7 +17,8 @@ import io.bartek.service.ServiceState
 
 
 class MainActivity : AppCompatActivity() {
-    private lateinit var controlServerButton: Button
+    private lateinit var controlServerButton: AppCompatImageButton
+    private lateinit var promptText: TextView
 
     private val receiver = object : BroadcastReceiver() {
         override fun onReceive(context: Context?, intent: Intent?) {
@@ -43,8 +46,14 @@ class MainActivity : AppCompatActivity() {
     private fun updateViewAccordingToServiceState(newState: ServiceState) {
         controlServerButton.isEnabled = true
         when (newState) {
-            ServiceState.STOPPED -> controlServerButton.text = getString(R.string.main_activity_run)
-            ServiceState.RUNNING -> controlServerButton.text = getString(R.string.main_activity_stop)
+            ServiceState.STOPPED -> {
+                controlServerButton.setImageResource(R.drawable.ic_power_off)
+                promptText.text = getString(R.string.main_activity_prompt_to_run)
+            }
+            ServiceState.RUNNING -> {
+                controlServerButton.setImageResource(R.drawable.ic_power_on)
+                promptText.text = getString(R.string.main_activity_prompt_to_stop)
+            }
         }
     }
 
@@ -52,6 +61,7 @@ class MainActivity : AppCompatActivity() {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
         controlServerButton = findViewById(R.id.control_server_button)
+        promptText = findViewById(R.id.prompt_text)
     }
 
     override fun onResume() {

app/src/main/res/drawable/ic_power_off.xml

@@ -0,0 +1,5 @@
+<vector android:height="200dp" android:tint="@android:color/darker_gray"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="200dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M13,3h-2v10h2L13,3zM17.83,5.17l-1.42,1.42C17.99,7.86 19,9.81 19,12c0,3.87 -3.13,7 -7,7s-7,-3.13 -7,-7c0,-2.19 1.01,-4.14 2.58,-5.42L6.17,5.17C4.23,6.82 3,9.26 3,12c0,4.97 4.03,9 9,9s9,-4.03 9,-9c0,-2.74 -1.23,-5.18 -3.17,-6.83z"/>
+</vector>

app/src/main/res/drawable/ic_power_on.xml

@@ -0,0 +1,5 @@
+<vector android:height="200dp" android:tint="@color/colorAccent"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="200dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M13,3h-2v10h2L13,3zM17.83,5.17l-1.42,1.42C17.99,7.86 19,9.81 19,12c0,3.87 -3.13,7 -7,7s-7,-3.13 -7,-7c0,-2.19 1.01,-4.14 2.58,-5.42L6.17,5.17C4.23,6.82 3,9.26 3,12c0,4.97 4.03,9 9,9s9,-4.03 9,-9c0,-2.74 -1.23,-5.18 -3.17,-6.83z"/>
+</vector>

app/src/main/res/layout/activity_main.xml

@@ -7,11 +7,19 @@
     android:orientation="vertical"
     tools:context=".MainActivity">
 
-    <Button
+    <TextView
+        android:id="@+id/prompt_text"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="20dp"
+        android:text="@string/main_activity_prompt_to_run"
+        android:textAlignment="center" />
+
+    <ImageButton
         android:id="@+id/control_server_button"
         android:layout_width="match_parent"
-        android:layout_height="0dp"
-        android:layout_weight="2"
+        android:layout_height="match_parent"
+        android:background="#00000000"
         android:onClick="controlServer"
-        android:text="@string/main_activity_run" />
+        app:srcCompat="@drawable/ic_power_off" />
 </LinearLayout>

app/src/main/res/values/strings.xml

@@ -3,6 +3,8 @@
 
     <string name="main_activity_run">Run</string>
     <string name="main_activity_stop">Stop</string>
+    <string name="main_activity_prompt_to_run">Tap power on button to run the server</string>
+    <string name="main_activity_prompt_to_stop">Tap power off button to stop the server</string>
 
     <string name="service_notification_category_name">HTTP Server</string>
     <string name="service_notification_category_description">The fixed notification keeping the HTTP server alive</string>